Commutator



May 6, 1930. J. M. CUNNINGHAM COMMUTATOR Filed Aug. 3," 1928 l Snowdon@gufi/ Hoz/M013 Patented 4May 6, 1930 UNITED A STATES PATENT OFFICEJAMES M. CUNNINGHAM. OF ENDICOTT. NEW' YORK, ASSIGNOB TO THE TABULATINGMACHINE COMPANY, F ENDICOTT, NEW YORK, A CORPORATION OF NEW 'JERSEYcoMMUTAToR The present invention relates broadly to a new and simplecommutator whereby the undesired consequences of sparking are reduced toa minimum.

ers are controlled by circuits established by brushes making a contactwith a contact baror roll. The cards are passed between the brushes andtheir associated contact and each time a perforation passes beneath asensing brush 1t makes a contact with ,its assoclated contact memberthrough said perforation.'

The circuit thus completed is an inductive circuit and as such is liableto cause'sparking at these sensing brushes. It has therefore been foundadvisable to make use of a comlnutator which is made up of contactsegmentswhich are wiped byy a brushof a more handy and durable naturethan the sensing brushes. This commutator is rotated in synchronism withthe feeding of thel card so that each index point position of therecordcard passing under the sensing brushes coincides with the passing of aContact segment of the commutatoz` under its coacting brush. Thespacingof these commutator segments are suchlthat the circuit iscompleted and broken lat the commutator and not at the sensing brushes.The sensing brush makes contact through the perforatlon followed by thecompletion of the circuit by the commutator and the commutator breaksthe circuit before the sensing brush leaves the perforation.

Applieation led August 3, 1928. Serial No. '297,132.

pense and of a material that will show the least amount of Wear. Whilein the foregoing description it has been shown how such a commutatorrelates to record controlled accounting machines it is understood thatsuch a construction could be used whenever a comnuvlt-ator is required.

The main object of the invention consists in the provision of plateglass inserts between the conducting parts of the commutator.

vide means to press the non-conducting inserts located between thecontact segments in a radial direction against the periphery ofl thecommutator.

A further object of the invention consists in the provision of a housingcomprising flange means to assemble the contact segments and the glassplate inserts which latter are pressed in a radial direction againstsaid overlapping means of the housing.

Other objects and advantages will be hereinafter' set forth in theaccompanying speci- 'ication and claims and shown in the drawings whichshow by way of illustration what I now consider to be one and apreferred embodiment of the invention.

Fig. 1 1s a sectional view of the commutator arranged on a shaft; l

Fig. 2 is a sectional view according to line 2 2 `of Fig. 1.

Referring to Fig. 1 fixed on a shaft 2 by means of a screw 3 is a sleeve4 serving. as carrier for the commutator assembly. Another sleeve 5consisting of insulating material is pressed upon sleeve 4 carryingthree disk rings 6, 7, and 8 provided around their periphery withtransverse flanges 9, 10, 11, and 12. Located between disk rings 6 and 7as Well as between disk rings 7 and 8 are cylinders 13, 14 of conductingmaterial as, for example, copper, each having a circumferential line ofround spring seats 15 and 16 formed therein each joining a cross-wise.

groove 17. The dimensions of the spring seats 15 and 16 are proportionedto accommodate pressure springs 18 while the grooves 17 accommodateglass inserts 19. Springs 18 press, as may be seen from Figs. 1 and 2,the

Another object of the invention is to pro- Y plate glass inserts 19against the flanges 9, 10, 11 and 12 of the disk rings 6, 7 and 8,whereby an easily assembled commutator with contact segments alternatingwith plate glass inserts between 'said segments is obtained.

Contact cylinders 13 and 14 are connected one with the other by rivets2O of conducting material thus providing an electrical connectionbetween two brushes slidingon the two commutators. `It will beunderstood, however, that one of the cylinders could be replaced by anordinary slip ring or that only one cylinder in electrical contact withits supporting shaft could be used.

While there have been shown and described and pointed out thefundamental novel fea# tures of the invention as applied to a singlemodification it will be understood that various omissions andsubstitutions and changes in the form and details of the deviceillustrated and in its operation may be made by those skilled in the artwithout departing from the spirit of the invention. It is the intention,therefore, to be limited only as indicated by the scope of the followingclaims:

1. A lcommutator consisting `ot' a plurality of contact segments and aplurality of plate glass inserts between said segments, means forassembling said contact segments and said plate glass inserts and springmeans to press the glass inserts in a radial direction against theperiphery of the commutator.

2. A commutator consisting of a plurality of contact segments formed ona complex cylinder by intermediate cuts, a plurality of plate glassinserts, means for assembling said Contact segments and said plateglass.

inserts, spring means to press the glass inserts in a radial directionagainst the periphery of the commutator, said plate glass inserts andspring means being located within said grooves. v

3. A commutator' consisting of a plurality of contact segments and aplurality of plate glass inserts between said segments, a housing withsidewalls vprovided with projecting 6. A commutator consisting of atube, an insulating tube pressed upon said first mentioned tube, aconducting cylinder arranged on said insulating tube and provided withtransverse cuts and a circumferential line of nature.

J. M. CUNNINGHAM.

flanges to assemble said contact segments and plate glass inserts, andspring means to press the plate glass inserts in a radial directionagainst said flanges.

4. A commutator consisting of a plurality of conducting segments, aplurality of nonlconducting inserts between said segments and means topress said inserts in a radial direcltion against the periphery of thecommutator. Y 5. A commutator consisting of a plurality of contactsegments formed on a complex cylinder by intermediate cuts, a pluralityof non-conducting inserts between said segments, spring means to pressthe non-conducting inserts in a radial direction against the peripheryof the commutator, said inserts and spring means being located withinsaid cuts.

